I was in Skuldafn Temple and a Draugr Deathlord shouted at me. I didn't notice at the time, but I picked up some kind of faint smoky spell effect from it and I cannot get rid of it. I thought it would fade over time or was part of the area I was in, so I went on. Now, I'm done with that area, am back in Ivarstead and still have that effect on me.

My Active Effects page shows no spell effects and removing all my gear/weaponry does not dispel it. How can I remove it, please?

First thing comes to my mind is quitting the game, and completely restarting computer and then game again. Second (easier, but smaller chance of success) is to
visit a shrine and take the cure, even though you don't have anything. Third is to cast Dispel on self. Fourth (and most likely) is to restart from before the Draugr
did it to you. Of course, you could always just change to first person view so you won't see the effects.